\documentclass{article}
\usepackage{amssymb,amsmath,amscd,concmath}
\pagestyle{empty}
\begin{document}
\begin{equation*}
\left \lfloor
 \frac{-415}{16}
\right \rfloor
=
\left \lfloor
 -25.9375
\right \rfloor
=
-26\end{equation*}
\end{document}
